| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package nmble |
| |
| import ( |
| "fmt" |
| "sync" |
| "time" |
| |
| "mynewt.apache.org/newtmgr/nmxact/nmxutil" |
| ) |
| |
| const syncPollRate = time.Second |
| |
| type Syncer struct { |
| x *BleXport |
| synced bool |
| enabled bool |
| |
| stopCh chan struct{} |
| syncCh chan bool |
| resetCh chan int |
| |
| wg sync.WaitGroup |
| |
| // Protects synced and enabled. |
| mtx sync.Mutex |
| } |
| |
| func (s *Syncer) Synced() bool { |
| s.mtx.Lock() |
| defer s.mtx.Unlock() |
| |
| return s.synced |
| } |
| |
| func (s *Syncer) setSyncedNoLock(synced bool) { |
| if synced == s.synced { |
| return |
| } |
| |
| s.synced = synced |
| s.syncCh <- synced |
| } |
| |
| func (s *Syncer) setSynced(synced bool) { |
| s.mtx.Lock() |
| defer s.mtx.Unlock() |
| |
| s.setSyncedNoLock(synced) |
| } |
| |
| func (s *Syncer) Refresh() (bool, error) { |
| s.mtx.Lock() |
| defer s.mtx.Unlock() |
| |
| if !s.enabled { |
| return false, fmt.Errorf( |
| "attempt to refresh sync state using disabled syncer") |
| } |
| |
| synced, err := SyncXact(s.x) |
| if err != nil { |
| return false, err |
| } |
| |
| s.setSyncedNoLock(synced) |
| return synced, nil |
| } |
| |
| func (s *Syncer) addSyncListener() (*Listener, error) { |
| key := TchKey(MSG_TYPE_SYNC_EVT, -1) |
| nmxutil.LogAddListener(3, key, 0, "sync") |
| return s.x.AddListener(key) |
| } |
| |
| func (s *Syncer) addResetListener() (*Listener, error) { |
| key := TchKey(MSG_TYPE_RESET_EVT, -1) |
| nmxutil.LogAddListener(3, key, 0, "reset") |
| return s.x.AddListener(key) |
| } |
| |
| func (s *Syncer) listen() error { |
| errChan := make(chan error) |
| |
| s.wg.Add(1) |
| go func() { |
| defer s.wg.Done() |
| |
| // Initial actions can cause an error to be returned. |
| syncl, err := s.addSyncListener() |
| if err != nil { |
| errChan <- err |
| close(errChan) |
| return |
| } |
| defer s.x.RemoveListener(syncl) |
| |
| resetl, err := s.addResetListener() |
| if err != nil { |
| errChan <- err |
| close(errChan) |
| return |
| } |
| defer s.x.RemoveListener(resetl) |
| |
| // Initial actions complete. |
| close(errChan) |
| |
| for { |
| select { |
| case <-syncl.ErrChan: |
| // XXX |
| case bm := <-syncl.MsgChan: |
| switch msg := bm.(type) { |
| case *BleSyncEvt: |
| s.setSynced(msg.Synced) |
| } |
| |
| case <-resetl.ErrChan: |
| // XXX |
| case bm := <-resetl.MsgChan: |
| switch msg := bm.(type) { |
| case *BleResetEvt: |
| s.setSynced(false) |
| s.resetCh <- msg.Reason |
| } |
| |
| case <-s.stopCh: |
| // It is OK to strand the two listeners. Their deferred |
| // removal will drain them. |
| return |
| } |
| } |
| }() |
| |
| return <-errChan |
| } |
| |
| func (s *Syncer) Start(x *BleXport) (<-chan bool, <-chan int, error) { |
| s.mtx.Lock() |
| defer s.mtx.Unlock() |
| |
| s.x = x |
| s.stopCh = make(chan struct{}) |
| s.syncCh = make(chan bool) |
| s.resetCh = make(chan int) |
| |
| s.synced = false |
| |
| if err := s.listen(); err != nil { |
| return nil, nil, err |
| } |
| |
| s.enabled = true |
| return s.syncCh, s.resetCh, nil |
| } |
| |
| func (s *Syncer) Stop() error { |
| initiate := func() error { |
| s.mtx.Lock() |
| defer s.mtx.Unlock() |
| |
| if !s.enabled { |
| return fmt.Errorf("Syncer already stopped") |
| } |
| |
| s.enabled = false |
| return nil |
| } |
| |
| if err := initiate(); err != nil { |
| return err |
| } |
| |
| s.synced = false |
| |
| close(s.stopCh) |
| |
| close(s.syncCh) |
| for { |
| if _, ok := <-s.syncCh; !ok { |
| break |
| } |
| } |
| |
| close(s.resetCh) |
| for { |
| if _, ok := <-s.resetCh; !ok { |
| break |
| } |
| } |
| |
| s.wg.Wait() |
| |
| return nil |
| } |